E-Linac Initiative: New Electron Driver for RIB Science Design for ½ MW SC linear accelerator driver for independent photo-fission production of RIBs Shane

E-Linac Initiative: New Electron Driver for RIB Science

Design for ½ MW SC linear accelerator driver for independent photo-fission production of RIBs

Shane Koscielniak, TRIUMF Accelerator Physicist International Peer Review, 24 September 2008

CANADA’S NATIONAL LABORATORY FOR PARTICLE AND NUCLEAR PHYSICSOwned and operated as a joint venture by a consortium of Canadian universities via a contribution through the National Research Council Canada

LABORATOIRE NATIONAL CANADIEN POUR LA RECHERCHE EN PHYSIQUE NUCLÉAIRE ET EN PHYSIQUE DES PARTICULES

Propriété d’un consortium d’universités canadiennes, géré en co-entreprise à partir d’une contribution administrée par le Conseil national de recherches Canada

2008 Sep 24 NRC International Peer Review 2

E-linac Talk Outline

• Introduction– Motivation/Impacts– Performance milestones– E-linac Specification

• Superconducting RF Because• Relation to TESLA/ILC

– ILC: voltage-gradient limited design– E-linac: power-gradient limited design

• Baseline design– High Power RF building blocks (2 slides)– Layout – functional & flexible– Capitalize on existing equipment designs

• Activity in support of design effort (3 slides)• Summary


New Science: Nuclear physics with neutron-rich RIBs, and 9Be(γ,p)8Li for β-NMR studies in Materials and Molecular Sciences.

Complementary & independent driver for RIB production.

Implements strategy of multiple beams (e, p) to multiple users to accelerate science output.

E-Linac will operate through annual cyclotron shutdowns providing strong year-round RIB experimental program.

Leverages valuable existing infrastructure: Proton Hall, shielded vault with servicesWorld-class experimental apparatus (detectors)Builds further SCRF expertise base from (β«1, 100 MHz, 4K) to (β=1, 1 GHz, 2K) - β=v/c relativistic speed

Prepares Canada for SCRF projects world-wide (ILC, CERN-SPL)

Qualifies commercial partner (PAVAC) to build SCRF cavities.

E-Linac Motivation/Impact


Performance milestones for RIB targets

Material in this e-linac talk covers Section 6-2-1-2-2 (pp 527-560) of the 5 Year Plan document.

Year E-linac capability Target capability

April 2010 – start of 5 Year Plan

2013 4 mA, ≥ 25 MeV (100 kW) 2 mA, ≥ 25 MeV (50 kW)

2014 4 mA, ≥ 25 MeV (100 kW)

April 2015 – start of next 5 Year Plan

2017 10 mA, ≥ 50 MeV (500 kW) 4 mA, ≥ 50 MeV (200 kW)

2019 10 mA, ≥ 50 MeV (500 kW)


Beam power (MW) 0.5

Duty Factor 100%

Average current (mA) 10

Kinetic energy (MeV) 50

E-Linac Specification

Photo-fission products distribution using 50 MeV 10 mA electrons on to Hg convertor & UCx target

Number of photo-fission /second versus electron energy for 100 kW e-beam on Ta convertor and U target.


Continuous operation is inconceivable with NC cavities – for 50 MeV, need 4-8 MW wall-plug power.

With SC cavities need ≤ 1.5 MW wall-plug power- enormous operational cost savings!

We chose Superconducting RF because:

Enormous world-wide effort in this regime since the 1990s dedicated to TESLA at DESY and now to International Linear Collider (ILC).

The Tesla Technology Collaboration (TTC) exists to promote, share and disseminate the remarkable results of the effort.

Technology is mature with gradients ≥ 20 MV/m routine.

Projects now include: DESY X-ray FEL, Cornell Energy Recovery Linac (ERL), Daresbury ERL Prototype, KEK-Free Electron Laser (FEL). KEK and FNAL efforts for ILC, Jefferson Lab upgrade, TRIUMF e-linac, etc.

TRIUMF joined TTC in April 2007.

We chose 1.3 GHz, 2K technology because:


DESY single-cell and 9-cell cavities form starting point for many SCRF linac designs around the world

ILC cavity module

Commonality of ILC with Fission Driver stops here and does not

extend to the cryomodule or High Power RF


ILC input coupler: ≤16kW average power

Fission Driver: 500 kW CW RF power has to propagate through input couplers and cavities to beam

E-linac input coupler: ≤60kW average power

Cornell/CPI-Eimac

E-linac: design driven by challenges of 100% duty factor high-power CW input coupler & limited choice of klystrons 2 kelvin heat loads in CW operation

Linear Collider: duty factor = 0.5%, design is limited by accelerating gradient (31.5 MV/m)


130 kW klystron

50 kW coupler

50 kW coupler

Beam current

Cavity gradient

# cavities Beam energy Beam power

5 mA 20 MV/m 3 60 MeV 300 kW

10 mA 10 MV/m 5 50 MeV 500 kW

20 mA 5 MV/m 10 50 MeV 1 MW

HP RF building block for e-linac

E-linac RF unit = 100 kW/cavity


e-GUN

BUNCHERCAVITY

BEAM TRANSPORT LINE

50 kW 50 kW

MAIN LINACCRYOMODULE #1

25 kW

INJECTORLINAC

e-GUN

BUNCHERCAVITY

BEAM TRANSPORT LINE

50 kW 50 kW 50 kW 50 kW

50 kW 50 kW 50 kW 50 kW

MAIN LINAC CRYOMODULE #2

MAIN LINACCRYOMODULE #1

50 kW

50 kW

INJECTORLINAC

E-linac in 2010-2015 plan100 kW, 25 MeV

E-linac in 2015-2020 plan500 kW, 50 MeV

E-linac power distribution

One 130 kW klystron/cavity


E-Linac Baseline Layout

Thermionic gun: triode; 100 keV; 650 MHz

NC buncher

Injector linac

10 MV/m, Q=1010

10 mA, 5-10 MeV gain≤ 100 kW beam pwr

Two cryomodulesTwo 9-cell cavities/module, 10 MV/m, Q=1010

10 mA, 40 MeV gain≤ 400 kW beam pwr

SRF Injector

Main linac

Focusing & diagnostic packages

Division into injector & main linacs allows: Possible expansion path to test-bed for

Energy Recovery Linac (ERL) – e.g. 10 mA, 80 MeVRecirculating Linear Accelerator (RLA) – e.g. 2 mA, 160 MeV

(acceleration & additional bunching)

Module #1 Module #2


Capitalize on existing equipment designsTESLA 9-cell cavities

Cornell/CPI 50 kW couplers e2V/CPI klystrons

Previous slides

Tuner: Costing based on INFN blade/coaxial tuner. XFEL industrialisation makes Saclay/lateral tuner a strong candidate.

RF-modulated Thermionic gun concept:NIKHEF-FELIX, Mistubishi

XFEL-type ceramic HOM loads, or Cornell-type ferrite loads

Normal conducting buncher cavity


International Comparison

Holifield Radioactive Ion Beam Facility, Oakridge:100 kW 25 MeV electrons provided by cascaded dual rhodotron accelerators. Presently, this proposal is active but unfunded.

ALTO at Orsay performs target yield studies with 5 kW capable LEPP Injector Linac – but limited by shielding to 10 uA 50 MeV.

E-linac is very competitive with respect to existing and other planned photo-fission based RIB facilities.


International ComparisonE-linac is a competitive and ambitious driver for γ-fission, yet in other arenas there are successful existing models for technical feasibility.

Light sourcesJefferson Lab IR-FEL: Accelerated (& energy recovered) up to 9.1 mA at 150 MeV.

Cornell ERL Injector prototype (100 mA, 5 MeV) is ready for beam tests.

Electron cooler ring for RHIC: proposed 22 MeV 0.5 Amp prototype Energy Recovery Linac

Hi-energy Physics


Activity in support of design effort

E-linac development started May 2007 Local task force drawn from Accelerator DivisionDeliverable: conceptual design and bottom-up resource estimation (manpower and M&S $) for all E-linac subsystems.Presentations, spread sheets, etc, at elinac.triumf.ca

Continuing seminar/visitor program:

Cornell: Charles Sinclair - electron gun; Cornell: Sergei Belomestnykh - SRF linacs & High Power RF NSF: John Weisend – cryomodule design & plant TJNAF/JLab: Ed Daly – crymodule design & costing LLNL: Brian Rusnak – high power input coupler design

Informal Review, 23 Jan 2008: Joe Preble (JLab), Paolo Pierini (INFN/Milan) – suggestions for cryomodule.


Activity in support of design effort

Proposal from Lawrence Livermore Lab to Dept Of Energy ONS for collaboration with TRIUMF on high-power CW coupler design for FRIB.Competition results announced ≈ November 2008.

Working with partners

VECC Kolkata collaboration: MoU covers equipment (2 horizontal test cryostats and 9-cell cavities) and personnel (2 FTEs, first arrives 1st November).

U. Toronto collaboration: 2 kelvin SCRF vertical test cryostat (see Laxdal/Grassellino talks)

Formal Review (Accelerator Advisory Cttee), 3-4 April 2008:Hasan Padamsee (Cornell), Sergei Nagaitsev (FNAL), M. de Jong (CLS), M. Schippers (PSI), M. Lindroos (CERN), Y. Yano (RIKEN), C. Sinclair (Cornell).


•June 23 – Canada Foundation for Innovation announces e-linac proposal designated as a National Project application

(not subject to institutional caps)

•June 30 - Official submission of Notice Of Intent to CFI signed by 14 Universities – lead institute = U.Victoria, Dean Karlen

•October 3 - Official deadline for full CFI application

Recent Successes

NIST/JLab electron gun donated to TRIUMF e-gun development station. Vacuum pumps and HV power supplies on order. Anticipate start beam characterization in 6 months.


Summary

E-Linac is central component of the TRIUMF 10-year vision.

The fission driver represents a major new RIB source – provides complementarity to proton-driven RIB production.

Suite of potential RIB applicationsNuclear/astro physicsMaterials & molecular sciencesLife/medical sciencesLight source technology test bed

SCRF technology provides cost effective approach to MW-class fission driver and capitalizes on world-wide R&D

Participate in ILC and other SCRF projects world wide

E-Linac is well-matched to the scale of the TRIUMF facility and its accelerator expertise.

We can build this machine.


For the back pocket?


E-Linac Capital

0 500 1000 1500 2000 2500 3000 3500 4000 4500

1

M&S (k$)

Beam Dynamics

Commissioning

QA plan & Proj docs

Proton Hall cleanup

Beam dump (50kW)

Cooling & Air service

Electrical Services

Controls

Personel Protection

Machine Protection

Beam Diagnostic

Alignment & Supports

Beamline

HOM absorbers

Tuners

Cavity Infrastructure

Cavity Fabrication

Cryovessel

Cryogenic Plant

HLRF

LLRF

Vacuum

Capture section

Buncher

eGun Total M$15.7


E-Linac human resources

0 20 40 60 80 100 120 140 160

1

months

Beam Dynamics

Commissioning

QA plan & Proj docs

Proton Hall cleanup

Beam dump (50kW)

Cooling & Air service

Electrical Services

Controls

Personel Protection

Machine Protection

Beam Diagnostic

Alignment & Supports

Beamline

HOM absorbers

Tuners

Cavity Infrastructure

Cavity Fabrication

Cryovessel

Cryogenic Plant

HLRF

LLRF

Vacuum

Capture section

Buncher

eGunTotal =108 years


Science Reviews

Policy and Planning Advisory Cttee (PPAC), 14-15 March 2008 - University input/priorization of 5YP components

Special Experimental Evaluation Cttee (SEEC), 25-26 March 2008-International review panel

Strong message from both: “get the science out early”.

Staging

Realization that greatest technical difficulty lies in the target station, not in the electron linear accelerator.

Target power handling will be staged: 100 kW in 5YP, ½ MW by end of 2015-2020 plan.

Consequences: E-linac beam power will be staged, and 1st beam delivery is advanced from 2014 to 2013.


Technical Summary

L-band SCRF technology provides cost effective approach to MW-class fission driver.

There are cell, cavity, input coupler, HOM damper, tuner, klystron, IOT, cryostat and BPM designs all pre-existing – eliminates substantial R&D & cost.

C.W. operation poses some challenges c.f. TESLA/ILC – but these are being met by ERL light source designs.

Minor changes since 5YP document reflect refinement of the e-linac design consistent with “earliest science” and restoring full flexibility of original 1+4 layout via 1+2+2 configuration.

Detailed costing and manpower estimation of the conceptual design gives confidence for 5YP and CFI requests


Minor change since 5YP document reflects refinement of the e-linac design consistent with “earliest science” and restoring full flexibility of original 1+4 layout via 1+2+2 configuration rather than 2+3 layout reported in 5YP.

2015

20132017

20132017

5YP

Original Concept

Refined Concept


CW operation has other challenges:Limited choice of c.w. klystrons, c.w. couplersHigher heat load in all RF components: cavity, input coupler, HOM coupler/absorber, etc

Fission driver, 10 MV/m

5 cavity

ERL

20 MV/m

3 cavity

TESLA TDR

23.4 MV/m

12 cavity

2K RF Load (W) 52 125 4.95

2K Sum (W) 56 189 9.05

5K Sum (W) 36.4 29 15.94

80K Coupler load 891 199 80.9

80K Sum (W) 897 451 183.02

Beam power related

CW related

E-Linac 2K & 80K sums are 5×TESLA values, but < ½ # cavities


Fission driver specification more relaxed than for ERL or ERL injector – many reasons!FEL light source at ERLs need 6D high-brillianceFEL e-beam time structure produces strong HOM loadingFission driver has no such requirements - eliminates beam on target

Daresbury ERLP

JLab IR-FEL (1.5 GHz)

Cornell ERL Injector

ILC Fission driver

Charge/bunch (pC) 80 135 80 100 16

Emittance (μm) normalized

1-2 <30 1 3/.03 100

Bunch length (ps) 1-2 0.2-2 2 2 30

Bunch rep’ rate (MHz)

81.25 75 1300 3 650

Macro-pulse rep’ rate (Hz)

20 c.w. c.w. 5 c.w.

Beam energy (MeV) 40 80-200 10 300/cryo 50


Documents

E-Linac Initiative: New Electron Driver for RIB Science Design for ½ MW SC linear accelerator driver for independent photo-fission production of RIBs Shane